anatomy ch 5 Flashcards
what does the integumentary system consist of
skin
hair
nails
sweat glands
sebaceous glands
epidermis
superficial region
epithelial tissue
avascular
dermis
underneath epidermis
fibrous connective tissue
vascular
hypodermis
subcutaneous layer
adipose tissue
absorbs shock and insulates
another name for hypodermis
superficial fascia
what type of epithelial cell makes up the epidermis
keratinized stratified squamous epithelium
what are the four cell types found in the epidermis
keratinocytes
melanocytes
dendritic cells
tactile cells
keratinocytes
produce keratin
connected via desmosomes
melanocytes
spider shaped
located in deepest epidermis
produce melanin
dendritic (langerhans) cells
star shaped macrophages
deep epidermis
key activators of immune system
tactile (merkel) cells
sensory receptors
how many layers thick is thick skin
5
hands and feet
how many layers thick is thin skin
4
what are the layers of skin from top to bottom
corneum
lucidum
granulosum
spinosum
basale
what layer of skin is only in thick skin
stratum lucidum
characterisitics of stratum basale
deepest layer
attached to dermis
single row of stem cells
actively mitotic (divides fast!!)
10-25% of layer composed of melanocytes
characteristics of stratum spinosum
prickly layer
several layers thick
resists tension and pulling
characteristics of stratum granulosum
granular layer
flattened cells, thin layer
TRANSITIONAL LAYER
keratinization begins
cells above what layer die
stratum granulosum
characteristics of stratum lucidum
found only in THICK SKIN
thin, translucent band of flat dead keratinocytes
stratum corneum
horny layer
20-30 rows
anucleated, keratinized
protection, prevent water loss
apoptosis
programed cell death
what are the two layers in the dermis
papillary
reticular
characteristics of the dermis
fibroblasts, macrophages, mast cells, white blood cells
contains nerves, blood vessels, lymphatic vessels
contains hair follicles, oil glands, sweat glands
papillary layer
superior layer of dermis
contains dermal papillae
dermal papillae
superficial region of dermis
fingerlike projections into epidermis
lie on top of dermal ridges
friction ridges
fingerprint pattern
reticular layer
lower layer of dermis
contains cleavage lines
cleavage (tension) lines
collagen fibers running parallel to skin surface
externally invisible
flexure lines
externally visible
reticular layer
what pigments contributes to skin color
melanin
carotene
hemoglobin
melanin
made in skin by melanocytes
freckles and moles made of local accumulations of melanin
made from amino acid tyrosine
carotene
yellow to orange pigment
most obvious in palms and soles
accumulates in stratum corneum and hypodermis
hemoglobin
contributes to pinkish hue of fair skin
cyanosis
blue skin color
low oxygen of hemoglobin
pallor
blanching, pale
erythema
redness (skin)
jaundice
yellow shin
hair
dead keratinized cells
aka pili
vellus hair
pale, fine body hair
children and adult females
terminal hair
course, long hair
scalp and eyebrows
axillary + pubic areas at puberty
nail matrix
thickened portion of nail bed responsible for nail growth
nail folds
skin folds that overlap border of nail
cuticle
nail fold that projects onto surface of nail body
another name for cuticle
eponychium
hyponychium
area under free edge of nail plate that accumulates dirt
lunule
half moon near cuticle
thickened nail matrix
appears white
sudoriferous glands
sweat glands
what are the two types of sweat glands
eccrine
apocrine
what cell type makes up sweat glands
myoepithelial cells
eccrine sweat gland characteristics
most numerous types
palms, soles, forehead
ducts connect to pores
secrete sweat
apocrine sweat gland characteristics
axillary and anogenital areas
bacteria breaks down sweat, producing SMELL
begins functioning at puberty
what are the two modified apocrine glands
ceruminous glands
mammary glands
ceruminous glands
lining of external ear canal
secretes cerumen (EARWAX)
mammary glands
secrete milk
sebaceous glands
secrete sebum
everywhere except for thick skin (palms, soles)
functions of skin
protection
body temperature regulation
cutaneous sensations
metabolic functions
blood reservoir
excretion of wastes
what are the three barriers in the skin
chemical
physical
biological
does the skin have a high or low pH
low pH
what are the three major types of skin cancer
basal cell carcinoma
squamous cell carcinoma
melanoma
basal cell carcinoma characterics
least malignant
most common
dermis and epidermis
surgical excision
squamous cell carcinoma characteristics
second most common type
keratinocytes of stratum spinosum
scaly reddened papule
melanoma characteristics
melanocytes
most dangerous type
highly metastatic & resistant to chemotherapy
ABCD rule
ABCD rule
for melanomas
A: asymmetry
B: border irregularity
C: color
D: diameter
first degree burn
epidermal damage only
localized redness
edema
pain
second degree burn
epidermal and upper dermal damage
blisters appear
partial-thickness burns
third degree burn
entire thickness of skin
skin color turns grey-white, red, blackened
nerve ending destroyed
need skin grafting
debridement
removal of burned skin
